Identifying the number of WS2 layers via Raman and photoluminescence spectrum

DOI

10.2991/icmmcce-17.2017.247How to use a DOI?

Keywords

WS2; Number of layers; Raman; Photoluminescence

Abstract

Recently, two-dimensional atomic layers of transition metal dichalcogenides (TMDs) have drawn more attention because of their remarkable electronic and optical properties. How to effectively identify the number of TMDs layers becomes an important issue. Here, we report the determination of the number of tungsten disulfide (WS2) layers using Raman scattering and photoluminescence (PL) spectrum. Under the excitation of 532 nm laser, the Raman scattering of WS2 shows rich spectrum information. With the number of layers increase, the peak of E1 2g( ) phonon mode of WS2 redshifts while the peak of A1g( ) blue shifts. For PL measurements, monolayer WS2 exhibits a performance of direct-bandgap. As the number of layers change from three to single, the PL peak intensity of WS2 increases, and the peak shifts to the short wavelength. Raman and PL mapping show coincident results. Our study establishes a systematical, noninvasive fingerprint path to identify different layers WS2 using Raman and PL spectrum simultaneously.

Copyright

© 2017, the Authors. Published by Atlantis Press.

Open Access

This is an open access article distributed under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/).

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TY  - CONF
AU  - Shuai Qiao
AU  - Hang Yang
AU  - Zongqi Bai
AU  - Gang Peng
AU  - Xueao Zhang
PY  - 2017/09
DA  - 2017/09
TI  - Identifying the number of WS2 layers via Raman and photoluminescence spectrum
BT  - Proceedings of the 2017 5th International Conference on Mechatronics, Materials, Chemistry and Computer Engineering (ICMMCCE 2017)
PB  - Atlantis Press
SP  - 1408
EP  - 1413
SN  - 2352-5401
UR  - https://doi.org/10.2991/icmmcce-17.2017.247
DO  - 10.2991/icmmcce-17.2017.247
ID  - Qiao2017/09
ER  -